1. Field of the Invention
The present invention relates to electronic equipment, such as computers and, more particularly, to an apparatus and method for providing electromagnetic interference (EMI) shielding to some of the electrical components of an electronic device.
2. Description of the Prior Art
Electronic components, such as printed circuit boards, generate electromagnetic interference (EMI) radiation. Such EMI radiation must be substantially prevented from escaping outwardly through the housing in which the electronic components are mounted. Moreover, it is also desirable that the EMI radiation generated by the electronic components be contained to avoid interfering with the operation of other electronic components. To this end, it has been proposed to mount printed circuit boards within a metallic chassis upon which a cover can be installed to provide EMI shielding. However, when it is desired to connect peripheral electronic devices, such as expansion cards, to the main printed circuit board of the device, one has first to remove the cover and thus unshield the main printed circuit board to have access to the electrical connectors thereof. The unshielded main printed circuit board can then be operatively connected to the peripheral device.
It would be desirable to have a new shielding structure in which individual electronic components are shielded from one another and are adapted to be connected to each other without having to be unshielded.
It is therefore an aim of the present invention to provide a shielding method and apparatus in which individual electronic components can be operatively connected without having to be unshielded.
It is also an aim of the present invention to provide a new shielding apparatus which facilitates the connection of an expansion card to a main printed circuit board of an electronic device.
It is a further aim of the present invention to provide a shielding apparatus for reducing the risk that respective electronic components of two electronic devices be damaged during installation procedures.
Therefore, in accordance with the present invention, there is provided a computer chassis in combination with a motherboard having at least one electrical connector extending from a surface thereof and to which additional electronic components are operatively connectable, comprising a support structure for supporting the motherboard, an EMI shield overlying said surface of said motherboard for shielding the motherboard from other electronic components, said support structure defining on a side of said shield opposite to said motherboard a space for receiving the additional electronic components, and at least one aperture defined in said shield for exposing said at least one electrical connector of the motherboard, thereby allowing the motherboard to be operatively connected to the additional electronic components without having to be unshielded.
In accordance with a further general aspect of the present invention, there is provided an electromagnetic interference (EMI) radiation shielded system for connecting at least one expansion card to a main printed circuit board of an electronic device, comprising a chassis, a main printed circuit board mounted within the chassis, an EMI shield overlying the main circuit board and defining one corresponding aperture for each electrical connector extending from the main printed circuit board, an EMI shielded loading cartridge housing an expansion card having at least one exposed connector accessible from outside said loading cartridge, said chassis defining a space for receiving said loading cartridge in a position wherein said at least one exposed connector of said expansion card operatively mates with a corresponding exposed connector of said main printed circuit board.
In accordance with a further general aspect of the present invention, there is provided a method of shielding interconnectable electronic components, comprising the steps of: mounting a first electronic component within a chassis behind an electromagnetic interference (EMI) shield defining one corresponding aperture for each electrical connector carried by the first electronic component, mounting a second electronic component in an EMI shielding module with a connector of said second electronic component remaining accessible from outside of said shielding module, mounting said EMI shielding module within said chassis with corresponding connectors of said first and second electronic components in mating engagement.
In accordance with a further general aspect of the present invention, there is provided a method of shielding electronic components, comprising the steps of: providing a number of electronic components on a planar board, providing an electromagnetic interference (EMI) radiation shielding plate, defining in said shielding plate one corresponding aperture for each electrical connector extending from said planar board, mounting said planar board and said shielding plate within a chassis with said shielding plate overlying said planar board and each said electrical connector in registry with a corresponding aperture in said shielding plate.